Psoas hematoma formation after violation of the intertransverse plane during posterior spinal surgery for adolescent idiopathic scoliosis.

Psoas hematoma is a rare yet potentially serious complication following posterior spinal surgery as it is a possible nidus for infection. We present a case of psoas hematoma formation following scoliosis surgery due to intraoperative violation of the intertransverse plane. A 13-year-old female patient with adolescent idiopathic scoliosis underwent a posterior deformity correction and instrumented fusion which was complicated with intraoperative inadvertent violation of the intertransverse plane during dissection of the posterolateral gutter leading to a unilateral psoas hematoma. She experienced abdominal pain and a CT scan confirmed the presence of a psoas hematoma. Antibiotic coverage was provided in view of positive blood culture of Bacillus species to avoid infective seeding of the hematoma. Resolution of the hematoma was observed on the reassessment CT one month postoperatively. It is not uncommon for patients to develop atrophic transverse processes due to spinal deformity. This may cause difficulties in identification of the anatomy intraoperatively and thus, extra caution should be exercised during dissection to prevent violation of the intertransverse plane and subsequent psoas hematoma complication.